Recognizing depression in patients with Parkinson’s disease: accuracy and specificity of two depression rating scale Reconhecimento de depressão em pacientes com doença de Parkinson: acurácia e especificidade de duas escalas de avaliação de depressão

This study aimed to find cut-off scores for the Montgomery-Asberg rating scale (MADRS) and the Beck depression inventory (BDI) that can relate to specific clinical diagnoses of depression in Parkinson´s disease (PD). Mild and moderate PD patients (n=46) were evaluated for depression according to the DSM IV criteria. All patients were assessed with the MADRS and the BDI. A "receiver operating characteristics" (ROC) curve was obtained and the sensibility, specificity, positive and the negative predictive values were calculated for different cut-off scores of the MADRS and the BDI. The Kappa statistic was calculated for different cut-off scores to assess the agreement between the clinical judgment and both scales. Depression was present in 18 patients. MADRS cut-off scores of 6 and 10 showed Kappa 0.5 and 0.56, respectively. Specificity of cut-off score of 6 was 78.6% and of cut-off score of 10 was 96.4%. Kappa agreement of BDI cut-off scores of 10 and 18 were 0.36 and 0.62, respectively. Specificity was 60.7% for 10 and 92.9% for 18. Both rating scales show similar accuracy within the ROC curves (84.3% for MADRS and 79.7% for BDI). The MADRS and the BDI show a good accuracy and correlation to the clinical diagnosis when a cut-off score of 10 is used to MADRS and a cut-off score of 18 is used to BDI to recognize depression in mild to moderate PD patients. This may help clinicians to recognize depression in PD.Este estudo objetivou encontrar pontos de corte da escala de depressão de Montgomery-Asberg (MADRS) e inventário de depressão de Beck (IDB) que possam estar relacionados ao diagnóstico clínico específico de depressão na doença de Parkinson (DP). Os pacientes com DP leve e moderada (n= 46) foram avaliados para depressão de acordo com os critérios diagnósticos da DSM-IV. MADRS e IDB foram aplicadas em todos os pacientes. Uma curva "receiver operating characteristics" (ROC) foi obtida calculando-se sensibilidade, especificidade, valores preditivos positivo e negativo para diferentes pontos de corte da MADRS e IDB. O índice Kappa foi calculado verificando-se a concordância entre o julgamento clínico e, ambas as escalas em diferentes pontos de corte. A depressão estava presente em 18 pacientes. Os pontos de corte 6 e 10 da MADRS evidenciaram índice Kappa de 0,5 e 0, 56 respectivamente. A especificidade para o ponto de corte 6 foi 78.6% e para o ponto de corte 10 foi 96,4%. O índice Kappa para os pontos de corte 10 e 18 do IDB foi 0,36 e 0,62 respectivamente.